Frequency Hopping

This paper introduces a new approach based on blind source separation (BSS) to mit igate intentional interference in BFSK d igital co mmun ication systems using frequency hopping spread spectrum technique. The use of BSS is possible thanks to adopting an adequate selection block to distinguish between the useful signal and other undesirable signals, hence, circu mvent the problem of amb iguity of permutation. An analytical calculation of the probability of error to predict the performance is done. The simulat ion results showed the effectiveness of this approach, whatever the level of the JSR and without using the fast frequency hopping alternative or error-correcting codes.

This paper introduces a new approach based on blind source separation (BSS) to mit igate intentional interference in BFSK d igital co mmun ication systems using frequency hopping spread spectrum technique. The use of BSS is possible thanks to adopting an adequate selection block to distinguish between the useful signal and other undesirable signals, hence, circu mvent the problem of amb iguity of permutation. An analytical calculation of the probability of error to predict the performance is done. The simulat ion results showed the effectiveness of this approach, whatever the level of the JSR and without using the fast frequency hopping alternative or error-correcting codes.

This paper introduces a new approach based on blind source separation (BSS) to mit igate intentional interference in BFSK d igital co mmun ication systems using frequency hopping spread spectrum technique. The use of BSS is possible thanks to adopting an adequate selection block to distinguish between the useful signal and other undesirable signals, hence, circu mvent the problem of amb iguity of permutation. An analytical calculation of the probability of error to predict the performance is done. The simulat ion results showed the effectiveness of this approach, whatever the level of the JSR and without using the fast frequency hopping alternative or error-correcting codes.

In this paper, the issue of Bluetooth and IEEE802.11b coexistence in a heterogeneous environment is addressed by means of an integrated analytical approach. The methodology proposed carefully takes both physical (i.e., thermal noise, propagation, interference, modulation formats, and coding techniques) and medium access control (frequency hopping, packet structures, traffic loads) aspects into account. This model can be easily implemented when developing network simulators, thus avoiding the need of extensive bit level Monte Carlo simulations at the physical level. The mean packet error probability is evaluated as a function of the relative distance between the two systems for different conditions (e.g., propagation, packet type, traffic loading, etc). In particular, how the presence or absence of line-of-sight propagation significantly affects the coexistence distance is emphasized. Furthermore, for a fixed quality-of-service level we derive the coexistence domain of the two considered systems in terms of relative distance.

The analysis and evaluation of jamming becomes very important with the strain of spectrum resources and the intensification of electronic countermeasures. In order to deepen the understanding of the mechanism of multitone jamming (MTJ) on multiple frequency shift keying and frequency-hopping (MFSK-FH) system, as well as support the communication equipment to improve the anti-jamming ability, the optimal MTJ pattern for a MFSK-FH system is analyzed in this paper. Firstly, the incoherent demodulation receiving model of MFSK-FH system under MTJ is established. Then, the optimal jamming channel, optimal jamming phase and optimal jamming tone number are discussed in detail. Finally, the simulation results of bit error rate (BER) performance are given.

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Berkembangnya teknologi informasi mengubah jalur komunikasi dari kabel menjadi non-kabel atau wireless. Banyaknya infrastruktur jaringan wireless yang telah ter-install dapat digunakan untuk berbagai kepentingan. Hal ini membuat pentingnya pemodelan terhadap sinyal wireless, karena berdasarkan kekuatan sinyal yang terpetakan dapat membantu memperoleh letak dari suatu objek yang menangkap sinyal tersebut. Pemodelan ini dikembangkan dengan menggunakan metode Finite- Difference Time-Domain (FDTD) yang biasa digunakan untuk merancang antena atau radar, bahasa pemrograman C++, dan visualisasi grafis dengan menggunakan OpenGL untuk memodelkan sinyal wireless yang dipancarkan dalam sebuah ruang. Perancangan model yang dikembangkan ini dapat membantu perancangan jaringan wireless dan pemetaan lokasi dalam suatu ruang. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-col...

A technique to estimate the performance of single site location (SSL) based on high-frequency direction finding for reigning ionospheric propagation conditions is described. This technique is based on classic propagation information (maximum useable frequency, frequency for optimum traffic, optimum working frequency, highest possible frequency, lowest possible frequency, etc.) which can be deduced by ray tracing through an ionospheric model such as the International Reference Ionosphere. The correlation between the elevation angle measured by an interferometric direction finder and the angles corresponding to the propagation conditions is used to assign a quality factor to the calculated SSL ground range result.

A technique to estimate the performance of single site location (SSL) based on high-frequency direction finding for reigning ionospheric propagation conditions is described. This technique is based on classic propagation information (maximum useable frequency, frequency for optimum traffic, optimum working frequency, highest possible frequency, lowest possible frequency, etc.) which can be deduced by ray tracing through an ionospheric model such as the International Reference Ionosphere. The correlation between the elevation angle measured by an interferometric direction finder and the angles corresponding to the propagation conditions is used to assign a quality factor to the calculated SSL ground range result.

Wireless LAN is wireless technology that can be used for voice and data communication. The increase of user requirement in Wireless LAN system caused the development of Wireless LAN increasing too. Standard of Wireless LAN is IEEE802.11a/b/g and IEEE802.11n use OFDM and MIMO technique for increase data rate without additional bandwidth. The purpose of this final project is to design physical layer of transmitter wireless LAN system to obtain gigabit throughput. Wireless LAN that we used now can produce rate up to 600 Mbps. So we expect this design of wireless system can increase data rate into gigabit throughput. The design of this system organized from arrangement of block diagram into preamble and data field. The data field, same as the previous standard, 802.11n consists of block scrambler, encoder parser, FEC encoder, interleaving, constellation mapper, spatial mapper, IFFT, cyclic shift, guard interval inserter and windowing. Whereas the preamble consists of legacy preamble is L -STF, L-LTF and L-SIG that have same format with previous standard in order to the output of transmitter 802.11ac can be compatible to 802.11a/n. Then, very high throughput preamble is added to this system as a preamble for 802.11ac. From the experiment result, we get the conclusion that wireless LAN 802.11ac is formed based on the previous standard 802.11a and 802.11n which have same frequency 5 GHz. Then, for 802.11ac we duplicate bandwidth from 40 MHz to 80 MHz and apply phase rotation. For the software verification backward compatibility, we determine the parameters 100 iteration, use MCS (Modulation Coding Scheme) 64 -QAM and 4 transmit antenna. As the result the 802.11ac transmitter can be recognized by 802.11a/n receiver and it can be shown as decreasing of SIG Error rate for SNR range 0-20 dB.

Perkembangan teknologi informasi yang pesat menuntut sistem komunikasi nirkabel yang andal, efisien, dan tahan terhadap gangguan. Salah satu pendekatan yang banyak digunakan untuk menjawab tantangan ini adalah Direct Sequence Spread Spectrum (DSSS) yang dikombinasikan dengan modulasi Binary Phase Shift Keying (BPSK) koheren. Penelitian ini bertujuan untuk merancang dan menganalisis performa sistem komunikasi digital berbasis DSSS-BPSK pada kanal Additive White Gaussian Noise (AWGN). Analisis dilakukan melalui simulasi yang mengevaluasi hubungan antara nilai Signal-to-Noise Ratio (SNR) dan Bit Error Rate (BER), serta mengamati pengaruh panjang kode pseudo-random terhadap ketahanan sistem. Hasil simulasi menunjukkan bahwa sistem DSSS-BPSK menunjukkan ketahanan yang baik terhadap derau, dengan nilai BER yang menurun signifikan seiring meningkatnya SNR. Selain itu, semakin panjang kode pseudo-random yang digunakan, semakin baik performa sistem dalam mengatasi gangguan kanal. Penelitian ini mendemonstrasikan efektivitas teknik penyebaran spektrum dalam meningkatkan reliabilitas komunikasi digital, khususnya pada lingkungan dengan kondisi kanal yang tidak ideal.

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Multipath fading, severe bandwidth limitation, non-Gaussian noise, and large propagation delays combine to make an underwater acoustic network (UAN) one of the more challenging ad hoc networking environments. It is important to refine the traditional networking protocols to optimize their performance for the given physical layer constraints of UANs [5]. One such refinement, the use of full-duplex channels, has been proposed for mitigating the performance penalties induced by large signal propagation delays that are inherent with UANs. Some full-duplex aerial acoustic communication capabilities were demonstrated recently [7]. However, due to the harsher physical environment in the ocean, the underwater acoustic research community in general was not convinced that the same level of performance would be attainable underwater. Furthermore, because of the scarcity of underwater acoustic bandwidth, bandwidth efficiency should not be sacrificed for the sake of fullduplex. This paper presents for the first time positive evidences that it is feasible to establish bandwidth efficient full-duplex underwater acoustic channels using Code Division Multiplex Access (CDMA) techniques.

This paper provides novel hardware design for frequency-hopping pseudorandom bit generator (PRBG).PRBG design by chaotic maps on FPGA.Two proposed methods in this work first combine chaotic maps in a cascade manner called fixed point cascade chaotic maps (FPCCM-FHSS), and second, the conjunction of chaotic maps done in an XORed manner called fixed point an XOR chaotic method (FPXORCM-FHSS).The results were the first eight NIST randomness tests.Frequency indicates that all p-values larger than 0.01 are needed to achieve better randomness, Second and third were die-hard tests, many distribution tests with significant p-values (p <0.01) that meet high standards of statistical randomness, making them suitable for channel security.Last were the FPGA results between the proposed methods for speed and hardware resources).The works implemented on XILINX ZC702 achieved 2 Gbps to meet the speed requirements of the change of the carrier frequency.

ABSTRAK Perkembangan teknologi pendukung EW = Electronic Warfare dan kebutuhannya dalam lingkungan pertempuran ( combat environment ). Spread spectrum yang merupakan suatu bentuk teknik modulasi, digunakan dalam peperangan modern untuk menghadapi gangguan (interferensi) dalam bentuk gelombang elektromagnetik oleh lawan terhadap aliran komunikasi. Spread spectrum untuk memenuhi tuntutan akan kebutuhan komunikasi yang handal, yaitu tahan terhadap interferensi dari luar, dapat beroperasi dengan rapat spektral daya rendah, menyediakan kemampuan akses jamak, dan tingkat keamanan yang tinggi. Direct Sequence Spread Spectrum (DSSS) adalah salah satu teknik spread spectrum (spektral tersebar), yaitu suatu jenis modulasi dimana lebar bidang frekuensi (band width) transmisi yang digunakan jauh lebih besar dari pada lebar bidang frekuensi minimum yang dibutuhkan untuk mentransmisikan informasi.

Abstrak Dalam sistem komunikasi proses modulasi dan demodulasi sangat berpengaruh terhadap proses pentransmisian sinyal, agar sinyal yang ditransmisikan sampai ke tujuan informasi. Modulasi adalah proses penumpangan sinyal informasi terhadap sinyal carrier, sedangkan demodulasi adalah proses konversi sinyal agar kembali kebentuk informasi semula setelah dimodulasikan. Pada saat ini akan dibuat simulator yang mensimulasikan sinyal analog, maka dari itu dibuat suatu sinyal AM untuk pembelajaran sinyal analog pada mata kuliah sistem komunikasi. Pada proyek akhir ini difokuskan pada pembuatan sebuah simulator untuk pembelajaran modulasi dan demodulasi AM dengan menggunakan MATLAB (Matrix Laboratory). MATLAB adalah software yang dapat dingunakan dalam proses pemrograman dengan menggunakan parameter pembentukan sinyal. Blok disimulasikan dari tahap pengiriman sampai deteksi disisi penerima melalui kanal AWGN (Additive White Gaussian Noise) dan kanal Rayleigh. Pada simulator ini yang telah...

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Real-time Radio Control (RC) systems require instantaneous response in the controlled device. RC systems have wide applications, including ad hoc networks. Imperfections in the wireless channel (noise and interference) result in randomly fluctuating latency in the response of the system. A lag occurs when the system latency exceeds a specified real-time threshold. System Lag Occurrence Probability (SLOP) is the probability of lag occurrence and is derived as the performance metric to characterize user experience in real-time radio control systems. Frequency hopping is used to mitigate interference effects. Uniform serial acquisition and N-state lock detection are used to simplify the derivation of SLOP. Simulation results are presented to verify the derivation of SLOP.

In this work, an asymmetric chaotic system with its circuit design and used for secure RADAR signal transmission. The chaotic system has four nonlinear terms, asymmetric behavior and wideband frequency spectra and large bandwidth. The chaotic signal/system is simulated in NI Multisim circuit design suite. The distinct and unique nature of chaotic signal can be utilized for RADAR communication to modulate the RADAR signal with the chaotic signal as a carrier signal. The chaotic modulation of the RADAR signal using the chaotic signal at the transmitter end via one the RADAR and demodulation is achieved at the receiver end via other RADAR and secure RADAR signal communication is accomplished. Numerical simulation is done in MATLAB and validated with achieved circuit simulation in NI Multisim which shows good agreement to that of MATLAB simulated results.

We employ the Mellin transform to facilitate the bit error ratio (BER) analysis of a fast frequency hopping (FFH)-assisted, M-ary frequency-shift keying (MFSK) using product combining (PC) when the transmitted signal is subjected to both Rayleigh fading and partial-band noise jamming. Exploiting the fact that the Mellin transform of the product of independent random variables is the product of their Mellin transforms, we derive the probability density function (PDF) of the PC's output. The derivation of the PDF then allows the computation of the system's BER. It is shown that the Mellin transform substantially simplifies the analysis of the PC receiver and hence facilitates, for the first time, the analysis of the FFH-MFSK PC receiver for modulation orders of M > 2.

A ray tracing program which is an algorithm that can be used to describe the complex nature of the ionosphere has been developed using locally available resources. The International Reference Ionosphere (IRI) Ionospheric Model were incorporated into the program for evaluating electron density values. Complex refractive indices of the ionosphere were generated using Appletone-Hartree formula with no collision and magnetic field effects. The program applies Snell's law of refraction in generating signal's refraction. 2-D ray coordinates were generated and ray path was plotted. The illustration in the application of the program was done using an assumed transmission of 6.957 MHz radio frequency from Abuja (7.38 o E, 8.99 o N) in the direction of Lagos (6.52 o N, 3.38 o E), Nigeria. Results provided amongst others includes, distribution of electron density (Ne) for the day and night time; minimum value of Ne at night (0:00 UT), ascending in the morning (6:00 UT), maximum at or close to noon (12:00-14:00 UT) and descending in the evening (18:00 UT). Rays travel farther distance in the solstice seasons than in the equinox seasons. Radio waves leaving the earth at high transmission angles above the horizon may receive only slight bending due to refraction, and are lost to outer space. It is hoped that the program will find immense application in High Frequency (HF) radio communication industries, research industries, aviation industries, and other industries that make use of Earth-Space systems.

A secure routing scheme for mobile wireless sensor networks such things as robots. For example, research into mobile WSNs are Robomote, 2 Emulab, 3 and ZebraNet. Challenges in mobile WSNs include deployment, localization, selforganization, navigation, coverage, and energy maintenance. One difference between static and mobile WSNs is routing, i.e., dynamic routing is used in a mobile WSN, unlike a static WSN which uses fi xed routing or fl ooding. The issue of security in WSNs must be addressed because WSNs may be deployed in potentially adverse or hostile environments. Adversaries can inject jamming, which may cause not only false alarms, but also depletion of the limited energy of sensor nodes. Frequency-hopping (FH) is a well-known spread-spectrum method of transmitting radio signals by rapidly changing the frequency channel using a predefi ned hopping sequence known to both transmitter and receiver. Although FH is resistant to jamming by external malicious nodes which have no knowledge of the sequence, it is of no effect against attacks by internal compromised nodes which know the sequence. Since the computation and storage constraints of low-end sensor nodes make complex cryptographybased mechanisms for creating the hopping sequence unfeasible, it is necessary to create the sequence simply and securely. In this article, we propose a secure scheme for creating a hopping sequence for mobile wireless sensor networks. The proposed scheme is based on the idea of statistical enroute fi ltering (SEF). In SEF, assuming that the same event can be detected by multiple nodes, forwarding nodes along the way to the base station can statistically detect false reports en-route. SEF has achieved the early detection of false data reports with low computation and communication overheads. We evaluated the performance of our scheme thorough simulations. The rest of the article is organized as follows. In Sect. 2, we describe the frequency-hopping and the statistical enroute fi ltering in detail. Section 3 presents our secure scheme for creating the hopping sequence for mobile wireless sensor networks. In Sect. 4, we evaluate the performance of our scheme thorough simulations, and Sect. 5 concludes the paper.

In this paper, a new approach is presented to derive the exact bit-error-rate (BER) performance of frequency-hopping spread-spectrum (FHSS) wireless networks with noncoherent M-ary frequency-shift keying (MFSK) in additive white Gaussian noise (AWGN) and Rayleigh fading channels. The new approach has enabled an exact evaluation of the BER, regardless of the modulation order M or the number of interferers. Theoretical results validated by simulations have shown that system performance is dominated by the first two hits, which lead to an accurate and computationally efficient approximation for the AWGN channel case. The exact and approximated results are compared with the simulation and semianalytic results presented in the literature.

A secure routing scheme for mobile wireless sensor networks such things as robots. For example, research into mobile WSNs are Robomote, 2 Emulab, 3 and ZebraNet. 4 Challenges in mobile WSNs include deployment, localization, selforganization, navigation, coverage, and energy maintenance. One difference between static and mobile WSNs is routing, i.e., dynamic routing is used in a mobile WSN, unlike a static WSN which uses fi xed routing or fl ooding. The issue of security in WSNs must be addressed because WSNs may be deployed in potentially adverse or hostile environments. Adversaries can inject jamming, which may cause not only false alarms, but also depletion of the limited energy of sensor nodes. Frequency-hopping (FH) is a well-known spread-spectrum method of transmitting radio signals by rapidly changing the frequency channel using a predefi ned hopping sequence known to both transmitter and receiver. 5,6 Although FH is resistant to jamming by external malicious nodes which have no knowledge of the sequence, it is of no effect against attacks by internal compromised nodes which know the sequence. Since the computation and storage constraints of low-end sensor nodes make complex cryptographybased mechanisms for creating the hopping sequence unfeasible, it is necessary to create the sequence simply and securely. In this article, we propose a secure scheme for creating a hopping sequence for mobile wireless sensor networks. The proposed scheme is based on the idea of statistical enroute fi ltering (SEF). 7 In SEF, assuming that the same event can be detected by multiple nodes, forwarding nodes along the way to the base station can statistically detect false reports en-route. SEF has achieved the early detection of false data reports with low computation and communication overheads. We evaluated the performance of our scheme thorough simulations. The rest of the article is organized as follows. In Sect. 2, we describe the frequency-hopping and the statistical enroute fi ltering in detail. Section 3 presents our secure scheme for creating the hopping sequence for mobile wireless sensor networks. In Sect. 4, we evaluate the performance of our scheme thorough simulations, and Sect. 5 concludes the paper.

The degradation of performance caused by Doppler shift to frequency hopped (FHYM-ary frequency shift keying (MFSK) ReedSolomon (RS) coded signal over a Rayleigh and Rician channel is analyzed. The receiver employs a digital processing scheme, consisting of an analog-to-digital (A D) converter followed by quadrature decomposition and complex-valued envelope discrete Fourier transformation (DFT). Predecoder symbol error probability and post-decoder word error probability are presented as a function of Doppler shift, channel randomness parameter, and the symbol energy-to-noise ratio. The noise is assumed to be white and Gaussian distributed. Results show that for a typical symbol error rate of the margin for 8-ary uncoded transmission must be increased by 8 dB to account for Doppler in a Rician fading channel.

In this paper, we analyze the error probability performance of an uncoded multicarrier frequency-hopping coherent binary phase-shift keying (MC-FH/BPSK) signal transmitted over a Rayleigh fading channel with multitone interference (MTI) and channel estimation errors. The channel estimation errors are modeled as Gaussian random variables. The performance in presence of worst case MTI is evaluated as a function of signal to noise ratio (SNR), signal to jamming ratio, and channel estimation errors. The effect of channel estimation errors on the error probability performance is investigated in presence and absence of MTI. It is shown, from the analytical results that when channel estimation errors are not neglected, the asymptotic error probability performance for high SNR exhibits an error floor even in the absence of MTI. Worst case MTI causes large increase in this error floor. It is also shown that increasing the subband order L enhances the system performance against multitone interference.

A Wireless Personal Area Network (WPAN) provides wireless networking among proximate devices, usually carried by an individual. Bluetooth is a first instance of the WPAN technology. The basic networking entity in Bluetooth is a piconet. Several piconets (WPANs) can be interconnected into a scatternet, which can be considered as an extendable multi-hop ad hoc networking structure. Since Bluetooth operates in the unlicensed ISM band, each piconet uses pseudorandom frequency hopping. If collocated piconets use the same channel simultaneously, the piconets interfere with each other and the transmitted packets are lost in collisions. This interference is termed self-interference. The piconets that are networked into scatternet exhibit spatial overlapping and naturally produce multi-piconet self-interference. The collisions cause retransmissions and increase the energy spent per data portion, which results in energy-inefficient operation. To tackle this problem, in our previous work we have proposed a self-interference avoidance (SIA) mechanism. However, this basic SIA mechanism is oblivious with respect to the physical topology and does not account for the mitigation of self-interference due to the propagation effects. Furthermore, the basic SIA mechanism relies on the assumption that all piconets are using packets of identical and fixed length. In this paper we will generalize the SIA mechanism to overcome the stated restrictions. We propose the adaptive SIA (A-SIA) algorithm, which adapts the SIA algorithm to the actual interference. The simulation results show that A-SIA largely retains the energy gain offered by the SIA algorithm, while significantly improving the goodput. We also design an instance of the SIA mechanism that operates with variable-length packets, referred as generalized SIA (G-SIA) algorithm. Our simulation results show that the G-SIA algorithm offers good performance in terms of goodput and energy efficiency, but the goodput is degraded if inappropriate segmentation/reassembly policy is used.

A secure routing scheme for mobile wireless sensor networks such things as robots. For example, research into mobile WSNs are Robomote, 2 Emulab, 3 and ZebraNet. Challenges in mobile WSNs include deployment, localization, selforganization, navigation, coverage, and energy maintenance. One difference between static and mobile WSNs is routing, i.e., dynamic routing is used in a mobile WSN, unlike a static WSN which uses fi xed routing or fl ooding. The issue of security in WSNs must be addressed because WSNs may be deployed in potentially adverse or hostile environments. Adversaries can inject jamming, which may cause not only false alarms, but also depletion of the limited energy of sensor nodes. Frequency-hopping (FH) is a well-known spread-spectrum method of transmitting radio signals by rapidly changing the frequency channel using a predefi ned hopping sequence known to both transmitter and receiver. Although FH is resistant to jamming by external malicious nodes which have no knowledge of the sequence, it is of no effect against attacks by internal compromised nodes which know the sequence. Since the computation and storage constraints of low-end sensor nodes make complex cryptographybased mechanisms for creating the hopping sequence unfeasible, it is necessary to create the sequence simply and securely. In this article, we propose a secure scheme for creating a hopping sequence for mobile wireless sensor networks. The proposed scheme is based on the idea of statistical enroute fi ltering (SEF). In SEF, assuming that the same event can be detected by multiple nodes, forwarding nodes along the way to the base station can statistically detect false reports en-route. SEF has achieved the early detection of false data reports with low computation and communication overheads. We evaluated the performance of our scheme thorough simulations. The rest of the article is organized as follows. In Sect. 2, we describe the frequency-hopping and the statistical enroute fi ltering in detail. Section 3 presents our secure scheme for creating the hopping sequence for mobile wireless sensor networks. In Sect. 4, we evaluate the performance of our scheme thorough simulations, and Sect. 5 concludes the paper.

Sending private messages over communication environments under surveillance is a very important challenge in communication security and has attracted a lot of attention from cryptographers through time. We believe that resources other than cryptographic keys can be used to provide communication privacy. We consider private message transmission (PMT) in an abstract multipath communication setting between two communicants, Alice and Bob, in the presence of a third-party eavesdropper, Eve. Alice and Bob have no a priori shared keys and furthermore, Eve is computationally unbounded. There are a total of n paths, and the three parties can have simultaneous access to at most ta, t b , and te paths. The parties can reselect their accessed paths after every λ bits of communication over a path. We study two types of perfect (P)-PMT and asymptotically-perfect (AP)-PMT protocols. The former has zero tolerance of transmission error and leakage, whereas the latter allows for positive error and leakage, which tend to zero as the message length increases. We derive the necessary and sufficient conditions (based on the above parameters) under which P-PMT and AP-PMT are possible. We also introduce explicit P-PMT and AP-PMT protocol constructions. Our results show that AP-PMT protocols attain much higher information rates than P-PMT ones. Interestingly, Alice and Bob can achieve AP-PMT even in unfortunate conditions that they have the least connectivity (ta = t b = 1) and Eve may access all but one paths (te = n -1). It remains however an open question whether the derived rates can be improved by more sophisticated AP-PMT protocols. We study applications of our results to private communication over the real-life scenarios of multiplefrequency links and multiple-route networks. We show practical examples of such scenarios that can be abstracted by the multipath setting: Our results prove the possibility of keyless information-theoretic private message transmission at rates 17% and 20% for the two example scenarios, respectively. We discuss open problems and future work at the end.